Fence Post Tar and Rocks/Pebbles?

Hi Everyone,

In reading some of the posts, many say tar the bottom of the fence post before putting it in concrete. The idea is that wood and concrete don't play well. Does this mean tar up the entire portion that would that sits in concrete?

What's the rule, 40% of the fence post should be in the ground? If so, then that means tar up 40% of the fence post?

Also, what kind of tar? Where do I get this tar that should go on the fence post?

Some have suggested putting pebbles in the bottom of the fence post hole to help with drainage. 2 inches of pebbles?

What about on the sides? Or do pebbles go in the sides as well?

If I use a 4x4 wood post, what should be the diameter of the hole?

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Fence Post Tar and Rocks/Pebbles?

Posts should definitely be pressure treated. CCA was rated at 40 years above ground, 20 years burried. Not sure about newer treatments. If setting in concrete, build the concrete up toward the post so water runs away from the post. Not necessarily tar, but any wood preservative brushed on the part below grade will help.

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Fence Post Tar and Rocks/Pebbles?

Reminds me of when I helped my father build a privacy fence around our back yard when I was a kid. This was in central California in the 1960s. I don't think pt lumber had even been invented yet.

The entire fence was redwood. Posts were 4x4s, and the ends were soaked in creosote for several days before setting them (I'm sure today's enviro-Nazis would love that). No concrete was used. That fence lasted more than 30 years.

Fence Post Tar and Rocks/Pebbles?

Quote:

Originally Posted by Just Bill

Posts should definitely be pressure treated. CCA was rated at 40 years above ground, 20 years burried. Not sure about newer treatments. If setting in concrete, build the concrete up toward the post so water runs away from the post. Not necessarily tar, but any wood preservative brushed on the part below grade will help.

When you say "wood preservative", do you mean something like Cabot's Wood Toner or something to stain the wood with? What are some examples of wood preservative that can or should be used?

Fence Post Tar and Rocks/Pebbles?

Reminds me of when I helped my father build a privacy fence around our back yard when I was a kid. This was in central California in the 1960s. I don't think pt lumber had even been invented yet.

The entire fence was redwood. Posts were 4x4s, and the ends were soaked in creosote for several days before setting them (I'm sure today's enviro-Nazis would love that). No concrete was used. That fence lasted more than 30 years.

Well I am still in California. Though, sometimes I wonder why I am still here considering how much California has changed. To me, in a lot of ways, it's really not the same.

In any case, the fence post I will be putting in is obviously for descent weather. At least where I am, it never snows. So I suppose I don't suffer from what some do: fence post heaving.